What does the term "permeability" refer to in insulation?

The term "permeability" in insulation specifically refers to the ability of a material to allow moisture to pass through it. This characteristic is crucial in the context of insulation because moisture can significantly affect the thermal performance and longevity of insulation materials. High permeability in insulation can result in moisture accumulation, which can lead to issues such as mold growth, reduced insulating capacity, and potential structural damage.

Understanding permeability is vital for insulators as they must select materials that not only provide effective thermal resistance but also appropriately manage moisture levels to maintain the integrity of both the insulation and the surrounding structures. It is important for insulators to consider the environment in which the insulation will be installed, ensuring the chosen material effectively balances thermal performance with moisture control.